| Potomac to Johnstown (Pennsylvania) | 128.97 mi (207.55 km) |
| Potomac to Joliet (Illinois) | 602.47 mi (969.58 km) |
| Potomac to Jonesboro (Arkansas) | 771.31 mi (1,241.31 km) |
| Potomac to Joplin (Missouri) | 949.75 mi (1,528.47 km) |
| Potomac to Joppatowne (Maryland) | 53.05 mi (85.37 km) |
| Potomac to Juana Díaz (Puerto Rico) | 1,584.08 mi (2,549.33 km) |
| Potomac to Junction City (Kansas) | 1,053.09 mi (1,694.79 km) |
| Potomac to Juneau (Alaska) | 2,812.89 mi (4,526.91 km) |
| Potomac to Jupiter (Florida) | 852.43 mi (1,371.86 km) |
| Potomac to Jupiter Farms (Florida) | 853.52 mi (1,373.60 km) |
| Potomac to Jurupa Valley (California) | 2,244.95 mi (3,612.90 km) |
| Potomac to Justice (Illinois) | 590.56 mi (950.42 km) |
| Potomac to Kahului (Hawaii) | 4,762.65 mi (7,664.75 km) |
| Potomac to Kailua (Hawaii) | 4,809.39 mi (7,739.97 km) |
| Potomac to Kalamazoo (Michigan) | 494.06 mi (795.11 km) |
